Plastic cap for compact fluorescent lamps

Abstract

The present invention provides a plastic cap ( 10 ) for fixing a glass body of a discharge tube of a compact fluorescent lamp in prescribed position by an adhesive material. The plastic cap is suitable for being fixed firmly to a housing of a fluorescent lamp base, and has a front plate ( 12 ) closing the inner space of the hollow housing or a part of the hollow housing of the fluorescent lamp base towards the discharge tube. As surface portions positioning the tube ends ( 34, 36, 38, 40, 42, 44 ) of the glass body of the discharge tube and fixing particular tube ends ( 38 ) firmly by an adhesive joint, seats ( 14, 16, 18, 20, 22, 24, 26, 28 ) with closed walls at least partly without perforations are indented into the front plate ( 12 ) of the cap ( 10 ). The seats ( 16, 20, 22, 26 ) only for positioning the tube ends ( 36 ) of the glass body have completely closed walls, while the seats ( 14, 18, 24, 28 ) also for fixing the tube ends ( 38 ) of the glass body by adhesive joint are provided with openings ( 50, 52, 54 ) suitable for introducing an adhesive material into the seats ( 14, 18, 24, 28 ) from the side of the front plate ( 12 ) opposite to the glass body of the discharge tube.

1 . A plastic cap for fixing a glass body of a discharge tube of a compact fluorescent lamp in prescribed position by a bonding material, the cap is suitable for being fixed firmly to a housing of a fluorescent lamp base and has a front plate closing the inner space of the hollow housing or a part of the hollow housing of the fluorescent lamp base towards the discharge tube; and surface portions are formed on the front plate for positioning at least some of the tube ends of the glass body of the discharge tube having at least one pair of tube ends and optionally also for increasing the mechanical strength of the adhesion joint between the tube ends and the cap wherein seats ( 14 ,  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ) with closed walls at least partly without perforations are as surface portions indented into the front plate ( 12 ) of the cap ( 10 ) in an arrangement corresponding to the geometry of the glass body of the discharge tube, the seats are fitted to the actual shape of the tube ends ( 34 ,  36 ,  38 ,  40 ,  42 ,  44 ) of the glass body for positioning the tube ends ( 34 ,  36 ,  38 ,  40 ,  42 ,  44 ) and also for fixing at least some of the tube ends ( 34 ,  38 ,  44 ) by means of adhesion joint; the seats ( 16 ,  20 ,  22 ,  26 ) only for positioning the tube ends ( 36 ,  40 ,  42 ) of the glass body have completely closed walls, while the seats ( 14 ,  18 ,  24 ,  28 ) also for fixing the tube ends ( 34 ,  38 ,  44 ) of the glass body by adhesion joint are provided with openings ( 50 ,  52 ,  54 ) suitable for introducing an adhesive material into the seats ( 14 ,  18 ,  24 ,  28 ) from the side of the front plate ( 12 ) opposite to the discharge tube.  
     
     
         2 . The plastic cap of  claim 1  in which at least one bag-like indentation, particularly a slot ( 78 ) is also formed in the surface of some seats ( 18 ,  24 ) fitting to the tube end ( 38 ), in the vicinity of the openings ( 50 ,  52 ).  
     
     
         3 . The plastic cap of  claim 2  in which the bag-like indentation ( 78 ) has a cross-section gradually decreasing from the opening ( 50 ,  52 ).  
     
     
         4 . The plastic cap of  claim 1  in which the bottom regions of some seats ( 14 ,  28 ) being adjacent to each other are also provided with at least one bore ( 30 , 32 ) for feeding through inleads of the discharge tube ends.  
     
     
         5 . The plastic cap of  claim 4  in which inlead-guiding funnels ( 70 ,  72 ,  74 ,  76 ) with diameters decreasing towards the bores ( 30 , 32 ) are formed in the bottom regions of the seats ( 14 ,  28 ) with bores ( 30 ,  32 ).  
     
     
         6 . The plastic cap of  claim 4  in which the adjacent seats ( 14 ,  28 ) with bores ( 30 ,  32 ) are provided with a common opening ( 54 ) formed for introducing an adhesive material, the common opening ( 54 ) extends into both seats ( 14 ,  28 ) simultaneously.  
     
     
         7 . The plastic cap of  claim 1  in which each opening ( 50 ,  52 ,  54 ) suitable for introducing an adhesive material is also provided with a funnel-like protrusion ( 56 ,  58 ,  60 ) being formed on the side of the front plate ( 12 ) opposite to the discharge tube and having cross-section narrowing towards the corresponding seat ( 14 ,  18 ,  24 ,  28 ).